I’d say any hair is probably going to work, and the choice ultimately depends on your technique and personal preference.
Personally, I’ve used both Western and Chinese brushes to paint Western watercolor. The Western brushes I use the most are squirrel and sable hair, plus the occasional ox hair brush for lifting. Of the Chinese brush hair types, goat hair compares to squirrel, being soft and absorbent. The biggest difference is that Chinese brushes have a more or less sharp tip, while the Western soft brush is usually a blunt mop/wash type. The Chinese “wolf” hair brush roughly corresponds to the Western sable brush, at least if we’re comparing good ones. A pure wolf brush is not really stiff or hard, just a bit elastic. Again, the tip of a Chinese brush is sharp, while Western sable brushes come in many shapes. I haven’t really used the very stiff and coarse hairs, but they might work for dry brush techniques. Ask yourself what you would like to paint.
For me, different brushes have their own special functions. For example, fine line brush made with weasel hair is mostly useful for small details while other brushes could hardly function the same way. For me, I always keep a simple but useful set of brushes, which include weasel hair brush, wool brush, and combination hair brush. There is one article on inkston about how to select proper brushes. I think you might find it helpful!